| 摘要 |
<p>PURPOSE:To prevent information from being read in an easy manner and to enable the informations to be read even if an information medium is damaged by a method wherein the information is provided with a hologram converted by a laser beam of a specific wavelength. CONSTITUTION:An information board 8 prestoring informations on its film is referred by a laser beam 1 of a specific wavelength to form an object beam 7 through a lens 5 and a mirror 4. A hologram 10 of the information held in the information board 8 is generated on an ID card 9 by the object beam 7 and an reference beam 6, which is of the same wavelength as the laser beam 1 and reflected through a half mirror 2 and a mirror 3. In the regeneration of the hologram 10, the hologram 10 is irradiated with the reference beam 6 which has been used in the generation of the hologram 10, whereby a regenerated beam 11 is formed, and the regenerated beam 11 is decoded by a hologram regeneration image reader 12 that is disposed so as to be symmetrical with respect to the informations board 8 with respect to the hologram 10, whereby the informations stored in the information board 8 is regenerated.</p> |
